Slip box



H. LEARY Sept. 21, 1954 SLIP BOX 2 Sheets-$heet 1 Filed March 31, 1952 Rm w W.

, HULL LEARY Hi5 HTTOQ EV SLIP BOX Filed March 31, 1952 2 Sheets-Sheet 2INVENTOR. uu. LEARY A? 4 TTO IVEV HIS H Patented Sept. 21, 1954 UNITEDSTATES PATENT OFFICE t SLIP BGX Hull Leary, Philadelphia, 'Pa.Application March 31, 1952, Serial No. 279,497

1 Claim.

My invention relates to slip boxes or mold jackets used to protect andreinforce squeeze molds during the pouring of steel castings or thelike.

The outside appearance of a sand mold after squeezing is quite generallythat of a truncated pyramid having sides tapering inwardly at an angleof approximately four degrees. The sand mold is given the angle of taperwhile being pressed in a squeeze machine during which time its sides areheld firm by a rigid flack whose sides are tapered at a four:degreeangle.

After squeezing, the mold is opened at the parting line to remove thepattern. When reassembling the sand mold it is necessary to replace thecope on the drag so that the mold conforms in all respects to the shapeit had prior to opening and the removalof the pattern.

if the reassembled sand mold does not exactly conform with the shape ithad prior to being parted, the castingproduced'will be shifted andtherefore unsatisfactory. The slip box which is placed over the moldafter reassembly must not in any manner disturb the relationship betweenthe cope and drag portions of the mold if a satisfactory casting is tobe obtained. If the taper of the slip boxes does not exactly conform tothe taper given the sand mold, the weight of a "rigid slip box willforce the cope or drag to "shift so that the sides of the sand mold willconform to the taper of the slip box resultin original taper of theflask but not necessarily uniformly. Thus, it is quite possible that oneor more sides may shift to an angle of, say, six degrees, while theremaining sides continue to have a taper of four degrees. It is apparentthat if a heavy, rigid'slip box having uniform sides is placed on a moldwhose sides vary from the true taper, the mold will be shifted or shavedto accommodate the .slip box.

The squeeze machine may .also distort the pins f the flask so that theouter perimeter of the cope does not exactly align itself with the outerperimeter of the drag. Such a condition resuitsina moldhavingacope withone side overhanging the corresponding side of the drag. When a rigidslip box is placed on such a mold the cope will be shiftedto alignitself with the drag but this shift will produce a shifted, andfrequently useless, casting.

In order to overcome the problem of shifting,

0 send mold with my slip box in place thereon;

in which 'I have contemplated various means have been introduced topermit the slip box to conform with the shape of the mold. These meanshave generally been unsatisfactory due to the fact that they requiredthat two sides of the slip box shift together, whereas the mold, and theflask which made the mold, may not have shifted the same amount onopposite sides of the mold or .fiask. A further difiiculty has beenspilling of the molten steelon the mold jacket with the consequentfreezing of the adjusting means, rendering the slip-box useless.Further, manual adjustment was required.

An object of my invention is to provide a slip box having sides whichmay be shifted inde pendently of any of the zother sides.

.A further object =of my invention is to provide a slip box which may beracked ior canted.

A still further nbject of "my invention is to provide a slip box withprotected shifting means.

A still further object of "my invention is to providea slip box whosepivotal centers will rest opposite 'the parting line of the mold.

The principles and characteristic features of my invention and themanner of making and constructing :and using my slip box will furtherappear in the accompanying drawings and the following descriptionexplaining the best modes using such principles.

Fig. 1 is a side elevational view of a tapered Fig. 2 is across-sectional,"elevational view of the mold and *slip box shown in'Fig. 1'; Fig. 3 is a perspective view -of my slip box with the sidesthereof angled at their greatest angle; Fig,

4 is an exploded view of one-side of the slip box together withtheangleirons corresponding therewith; Fig. 5 is a fragmentary view of acorner of my slip'box's'howing the position of the taken along the line8-58 ofFig. 6 'Fig. 9 is va fragmentary view of "a corner of amodifiedform of slip box wherein an additional pivot point is provided for amold having a cope and drag of unequal depth; Fig. 10 is an elevationalview of a mold havingone side with a different angle of taper from itsopposite side; Fig. 11 is an elevational view of a mold wherein the copehas been laterally displaced with relation to the drag; and Fig. 12 is aplan view of a mold having racked sides.

The slip box comprises tapered plates I, joined by angle irons 2 havingopenings 3 and 4 inter-. mediate the ends thereof. Spaced openings 5 ofthe same diameter as the holes 3 are provided in the plates I oppositethe openings 3 and 4 through which bolts 6 are passed and secured bynuts I. The-pivot or parting line openings 3 and the openings 5 are ofapproximately the same diameter as the bolts 6 but the openings 4 arepreferably about twice the diameter of the bolts 6. Thus, each sideplate I is able to turn or pivot an amount equal to the difierencebetween the diameter of the holes 3 and 4.

The perfect mold has sides58 and 9 (Fig. 1) which taper inwardly at thesame angle, 4 degrees, and has a cope which registers exactly on thedrag. Where, however, a mold is formed in a flask having sides ofdifferin angles of taper a mold is produced which may be similar to thatshown in Fig. 10 wherein the side I0 tapers inwardly ata substantiallygreater angle than the opposite side II. If a slip box having rigidsides is placed on such a mold, it will force the mold to assume theshape of the slip box either by shaving off the distorted side or bycompressing the mold.

A distorted flask or flask pin may form a mold in which the cope I2 isoffset on the drag I 3 as illustrated in Fig. 11. If a slip box havingrigid sides is placed on such a mold, it will shift the cope or draguntil the sides of the cope register with the sides of the drag.

In either of the above instances the pattern formed by the core (notshown) will'be shifted and the casting poured from such a mold will beimperfect.

In my slip box the side plate I may be angled about the pivot bolts 6 toaccommodate any reasonable distortion in the mold. In order to pivot,the side plate I turns about the two pivot bolts 6 contained in the faceof the angle irons which are at'right angles to the plane of the sideplate to be moved. The amount ofturning is limited by the size of theopenings =4 oreby the distance between the rear-face I8 of the angleirons in the plane of the plate being pivoted and the end of the Sideplates perpendicular ,to the side plate being pivoted, as shown in Figs.5 and 6. The nuts I are secured to the bolts 6 in such manner that theplatesI are able to'move along the face of the angle irons 2 withoutundue friction.

Each of the plates I and angle irons 2 are completely interchangeableand readily replaceable andcan be assembledor disassembled and stored ina minimum amount of time and space. Should one of the plates bedistortedaccidentally it can be readily removed and replaced by another thusresulting in slip boxes which give a maximum amount of use and a minimumamount of discards,

I protect the angle irons and bolts from being frozen by molten metal byproviding a splash plate I4 along the top of each angle iron. When, assometimes happens, molten metal is spilled the splash plate Ill shieldsth bolts 6 and nuts I from molten metal and eliminates the possibilityof immobilization of, the slip box.

I provide for the openings 3 to be at the parting line H of the mold asthis provides a point about which maximum effect is derived from thepivoting. Because of the shape of the article to be cast, it is notalways possible to use a mold having the same depth of cope as of drag.I have provided for this contingency by having additional pivot pointopenings I5 in the side plates and angle irons Fig. 9. By shifting thepivot bolt from opening 3 to opening IE, or the reverse thereof, Iprovide more cover protection to the cope or to the drag as may bedesirable, thus reducing the number and variety of slip boxes which mustbe kept in inventory. R

It sometimes happens that a mold is formed which is out of square. Mybox can rack sufficiently to accommodate out of square boxes or toaccommodate buckling due to heat. This is possible because of thesubstantially friction free relationship between the'angle irons and thesides. A mold such as described is illustrated in Fig. 12.

Rigid slip boxes are frequently burned and buckled when hot gasesattempt to escape from the mold during the pouring operation. My slipboxes allow these hot gases to escape harmlessly at each corner inasmuchas a venting space I6 is provided at each corner of the box. As the hotgasses can escape easily and quickly up these vents the danger ofoverheating the slip boxes and consequent buckling is substantiallyeliminated.

It is to be understood that I have merely illustrated the preferredembodiment of my invention and the provision of additional pivotopenings or variations in the placement of the safety openings 4 are notoutside the scope of this invention.

Having described my invention I claim:

An automatically adjustable slip box for a tapered mold comprising aplurality of rectangular plates having a plurality, of identically sizedapertures adjacent the longitudinal extremities, one of said aperturesat each of said extremities being located on approximatel thelongitudinal axis of saidplates, a plurality of angle irons connectingsaid plates and having apertures in juxtaposition to the apertures insaid plates, the apertures in said angle irons opposite the apertures onthe longitudinal axis of said plates being of substantially the samesize as the apertures in said plates and the-remaining angle ironapertures being substantially larger than said plate apertures, screwbolts projecting through said apertures and nuts loosely applied tosaid'screw bolts permitting the said plates to freely and independentlypivot about said bolts in the apertur-es along said longitudinal axisfor automatic adjustment to the taper of said molds.

References Cited in the file of this patent UNITED STATES PATENTS

